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    //! A newtype with alignment of at least `A` bytes
    //!
    //! # Examples
    //!
    //! ```
    //! use std::mem;
    //!
    //! use aligned::{Aligned, A2, A4, A16};
    //!
    //! // Array aligned to a 2 byte boundary
    //! static X: Aligned<A2, [u8; 3]> = Aligned([0; 3]);
    //!
    //! // Array aligned to a 4 byte boundary
    //! static Y: Aligned<A4, [u8; 3]> = Aligned([0; 3]);
    //!
    //! // Unaligned array
    //! static Z: [u8; 3] = [0; 3];
    //!
    //! // You can allocate the aligned arrays on the stack too
    //! let w: Aligned<A16, _> = Aligned([0u8; 3]);
    //!
    //! assert_eq!(mem::align_of_val(&X), 2);
    //! assert_eq!(mem::align_of_val(&Y), 4);
    //! assert_eq!(mem::align_of_val(&Z), 1);
    //! assert_eq!(mem::align_of_val(&w), 16);
    //! ```

    #![deny(missing_docs)]
    #![deny(warnings)]
    #![cfg_attr(not(test), no_std)]

    use core::ops;

    use as_slice::{AsMutSlice, AsSlice};

    mod sealed;

    /// 2-byte alignment
    #[repr(align(2))]
    pub struct A2;

    /// 4-byte alignment
    #[repr(align(4))]
    pub struct A4;

    /// 8-byte alignment
    #[repr(align(8))]
    pub struct A8;

    /// 16-byte alignment
    #[repr(align(16))]
    pub struct A16;

    /// A newtype with alignment of at least `A` bytes
    pub struct Aligned<A, T>
    where
        T: ?Sized,
    {
        _alignment: [A; 0],
        value: T,
    }

    /// Changes the alignment of `value` to be at least `A` bytes
    #[allow(non_snake_case)]
    pub const fn Aligned<A, T>(value: T) -> Aligned<A, T> {
        Aligned {
            _alignment: [],
            value,
        }
    }

    impl<A, T> ops::Deref for Aligned<A, T>
    where
        A: sealed::Alignment,
        T: ?Sized,
    {
        type Target = T;

        fn deref(&self) -> &T {
            &self.value
        }
    }

    impl<A, T> ops::DerefMut for Aligned<A, T>
    where
        A: sealed::Alignment,
        T: ?Sized,
    {
        fn deref_mut(&mut self) -> &mut T {
            &mut self.value
        }
    }

    impl<A, T> AsSlice for Aligned<A, T>
    where
        A: sealed::Alignment,
        T: AsSlice,
    {
        type Element = T::Element;

        fn as_slice(&self) -> &[T::Element] {
            T::as_slice(&**self)
        }
    }

    impl<A, T> AsMutSlice for Aligned<A, T>
    where
        A: sealed::Alignment,
        T: AsMutSlice,
    {
        fn as_mut_slice(&mut self) -> &mut [T::Element] {
            T::as_mut_slice(&mut **self)
        }
    }

    #[test]
    fn sanity() {
        use core::mem;

        let x: Aligned<A2, _> = Aligned([0u8; 3]);
        let y: Aligned<A4, _> = Aligned([0u8; 3]);
        let z: Aligned<A8, _> = Aligned([0u8; 3]);
        let w: Aligned<A16, _> = Aligned([0u8; 3]);

        // check alignment
        assert_eq!(mem::align_of_val(&x), 2);
        assert_eq!(mem::align_of_val(&y), 4);
        assert_eq!(mem::align_of_val(&z), 8);
        assert_eq!(mem::align_of_val(&w), 16);

        assert!(x.as_ptr() as usize % 2 == 0);
        assert!(y.as_ptr() as usize % 4 == 0);
        assert!(z.as_ptr() as usize % 8 == 0);
        assert!(w.as_ptr() as usize % 16 == 0);

        // test `deref`
        assert_eq!(x.len(), 3);
        assert_eq!(y.len(), 3);
        assert_eq!(z.len(), 3);
        assert_eq!(w.len(), 3);

        // alignment should be preserved after boxing
        let x: Box<Aligned<A2, [u8]>> = Box::new(Aligned([0u8; 3]));
        let y: Box<Aligned<A4, [u8]>> = Box::new(Aligned([0u8; 3]));
        let z: Box<Aligned<A8, [u8]>> = Box::new(Aligned([0u8; 3]));
        let w: Box<Aligned<A16, [u8]>> = Box::new(Aligned([0u8; 3]));

        assert_eq!(mem::align_of_val(&*x), 2);
        assert_eq!(mem::align_of_val(&*y), 4);
        assert_eq!(mem::align_of_val(&*z), 8);
        assert_eq!(mem::align_of_val(&*w), 16);

        // test deref-ing
        let x: Aligned<A2, _> = Aligned([0u8; 3]);
        let y: &Aligned<A2, [u8]> = &x;
        let _: &[u8] = y;
    }

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